In Fig. 3, we show the DFT results for CGT/BLG/CGT with
an average equilibrium interlayer spacing \(d=3.65~{Å}\)  between CGT monolayer
and its close-contacted graphene monolayer. The unit cell in Fig. 3(a) is constructed with a \(5\times 5\)  supercell of 50 carbon atoms per graphene layer and a \(\sqrt{3}\times \sqrt{3}\)  supercell of 12 chromium atoms per CGT layer. See Appendix D for other computable details. To clarify the magnetism of the ground state, we show the energy difference on average per atom (\(\Delta E\) ) between the FM and LAF states in Fig. 3(b), which strongly suggests that the system has a LAF ground state robust against small \(E_z\)  that we focus on. In contrast, bilayer CGT itself is FM [1]}, which becomes LAF
here when the layers are spatially separated.
